(c)
a surface abutting the end of the strip associated with runway approach 18 consisting of an inclined plane having a ratio of one (1) metre measured vertically to forty (40) metres measured horizontally rising to an intersection with the outer surface thence said approach surface shall be contiguous to said outer surface to an intersection with the northern extremity of said outer surface, said intersection being on the projected centre line of the strip and distant three thousand eight hundred and fifty (3 850) metres from the end of the strip, the outer end of said approach surface shall be an imaginary horizontal line drawn at right angles to the projected centre line of the strip, the outer ends of the imaginary horizontal line being seven hundred and twenty-seven decimal five (727.5) metres from the projected centre line, said imaginary horizontal line being forty-five (45) metres, measured vertically, above the airport reference point; and